A non-contact power supply system which transfers power without using a power cable has been used in recent years. The non-contact power supply system is capable of supplying electric power to a secondary battery carried on a personal computer, an AV (Audio Visual) device and the like with the use of the resonance phenomenon of an electromagnetic field.
Further, it is researched to introduce such a non-contact power supply system into a peripheral device of a POS (Point Of Sale) system. In a case in which a non-contact power supply system is introduced into a POS system, the peripheral device cannot be charged if a non-contact charger is not placed at a chargeable position. However, there is a case in which an operator of the POS system neglects or unintentionally forgets to place the peripheral device at a chargeable position because he/she always gives priority to sales-register the commodities.